[FAB-1862] - send block event after commit

This change set ensures that block events are generated only *after* the
block has been committed to the ledger (and not before as it was the case
previously).

Change-Id: I25bab47cc7d69b6e804fc605cf7710dca0050d21
Signed-off-by: Alessandro Sorniotti <ale.linux@sopit.net>

core/committer/committer_impl.go

@@ -17,8 +17,11 @@ limitations under the License.
 package committer
 
 import (
+	"fmt"
+
 	"github.com/hyperledger/fabric/core/committer/txvalidator"
 	"github.com/hyperledger/fabric/core/ledger"
+	"github.com/hyperledger/fabric/events/producer"
 	"github.com/hyperledger/fabric/protos/common"
 	pb "github.com/hyperledger/fabric/protos/peer"
 	"github.com/op/go-logging"
@@ -60,6 +63,13 @@ func (lc *LedgerCommitter) Commit(block *common.Block) error {
 	if err := lc.ledger.Commit(block); err != nil {
 		return err
 	}
+
+	// send block event *after* the block has been committed
+	if err := producer.SendProducerBlockEvent(block); err != nil {
+		logger.Errorf("Error sending block event %s", err)
+		return fmt.Errorf("Error sending block event %s", err)
+	}
+
 	return nil
 }
 

core/deliverservice/client.go

@@ -22,7 +22,6 @@ import (
 
 	"github.com/golang/protobuf/proto"
 	"github.com/hyperledger/fabric/core/committer"
-	"github.com/hyperledger/fabric/events/producer"
 	gossipcommon "github.com/hyperledger/fabric/gossip/common"
 	gossip_proto "github.com/hyperledger/fabric/gossip/proto"
 	"github.com/hyperledger/fabric/gossip/service"
@@ -219,10 +218,6 @@ func (d *DeliverService) readUntilClose() {
 			// Gossip messages with other nodes
 			logger.Debugf("Gossiping block [%d], peers number [%d]", seqNum, numberOfPeers)
 			service.GetGossipService().Gossip(gossipMsg)
-			if err = producer.SendProducerBlockEvent(t.Block); err != nil {
-				logger.Errorf("Error sending block event %s", err)
-			}
-
 		default:
 			logger.Warning("Received unknown: ", t)
 			return